The research which we now propose to carry out covers a synthetic area of natural products chemistry. The proposal includes: (1) total synthesis of ansamycin antibotics, rifamycin (2) total synthesis of polyether antibiotics, narasin, (3) total synthesis of optically active gephyrotoxin, (4) total synthesis of gonyautoxins, (5) total synthesis of histrionicotoxin, and (6) total synthesis of palytoxin. We belive these proposed studies of natural products will very effectively extend the scope of synthetic organic chemistry.